The present invention relates to broadcast spreaders for particulate materials, such as fertilizer, and more particularly to hopper discharge and pattern controlling components thereon.
It is important for a broadcast spreader to provide predictable and generally even distribution patterns and application rates. The shape and the size of the area of ground covered as the spreader advances need to be what the operator expects them to be, and the amount of material laid down in any selected location covered by the spreader needs to be substantially the same as the amount laid down in every other location.
Another performance attribute is versatility, both in terms of the spreader being suitable for use with a wide variety of materials and in terms of its being able to provide a wide range of application rates. Heretofore, however, versatility beyond a conventional range of materials a and/or flow rates could not be obtained without a significant loss in the predictability and evenness of distribution. Larger sized or more densely applied particulate materials such as lime, sand, ice melting products and some agricultural fertilizers were particularly troublesome for conventional spreaders known to the present inventor. Such substances could only be applied, if at all, by making several passes over the ground to be covered or by allowing for a relatively skewed distribution pattern. Thus, the present inventor was faced with the problem of devising a broadcast spreader that would provide predicable and even distribution patterns and rates, not only for conventional materials, but also for larger and more densely applied particulates.